Answer:
Average speed of the trip = 52.9 km/h
Distance between initial pairs of cities (start to end) = 70.0 km
Explanation:
Since distance = speed × time
If she drives 30.0 min at 80.0 km/h
Distance covered = (30/60) × 80 = 40.0 km
Again she drives 45.0 min at 40 km/h
Distance covered = (45/60) × 40 = 30.0 km
Again she drives 12.0 min at 100 km/h
Distance covered = (12/60) × 100 = 20.0 km
Total distance covered = 40.0 + 30.0 + 20.0
= 90.0 km
Total time spent = 30.0 + 45.0 + 12.0 +15.0
= 102 min
Average speed for the trip = Total distance covered/total time spent
= 90/(102/60)
= 52.9 km/h
Distance between initial cities will be between the start of one city to the end of another
Between the first pairs = 40.0 + 30.0 = 70.0 km
Between the second pairs = 30.0 + 20.0 = 50.0 km
Let F = the downstream speed of the water.
<span>Then the boat's upstream speed is: 15 - F </span>
<span>The boat's downstream speed is: 15 + F </span>
<span>Assume both the journeys mentioned take T hours, then using "speed x time = distance" we get: </span>
<span>Downstream journey: (15 + F)T = 140 </span>
<span>Upstream journey: (15 - F)T = 35 </span>
<span>Add the two formulae together: </span>
<span>(15 + F)T + (15 - F)T = 140 + 35 </span>
<span>15T + FT + 15T - FT = 175 </span>
<span>30T = 175 </span>
<span>T = 35/6 </span>
<span>Use one of the equations to find F: </span>
<span>(15 + F)T = 140 </span>
<span>15 + F = 140/T </span>
<span>F = 140/T - 15 </span>
<span>F = 140/(35/6) - 15 </span>
<span>F = 24 - 15 </span>
<span>F = 9 </span>
<span>i.e. the downstream speed of the water is 9 kph </span>
<span>Therefore, the boat's speed downstream is 15 + F = 15 + 9 = 24 kph.
the answer is: *24kph*</span>
Phase 1. Forethought/preaction—This phase precedes the actual performance; sets the stage for action; maps out the tasks to minimize the unknown; and helps to develop a positive mindset. Realistic expectations can make the task more appealing. Goals must be set as specific outcomes, arranged in order from short-term to long-term. We have to ask students to consider the following:
<span>When will they start?Where will they do the work?How will they get started?<span>What conditions will help or hinder their learning activities are a part of this phase?
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Phase 2. Performance control—This phase involves processes during learning and the active attempt to utilize specific strategies to help a student become more successful.
We have to ask students to consider the following:
<span>Are students accomplishing what they hoped to do?Are they being distracted?Is this taking more time than they thought?Under what conditions do they accomplish the most?What questions can they ask themselves while they are working?<span>How can they encourage themselves to keep working (including self-talk—come on, get your work done so you can watch that television show or read your magazine!)
</span></span>
Phase 3. Self-reflection—This phase involves reflection after the performance, a self-evaluation of outcomes compared to goals.
We have to ask students to consider the following:
<span>Did they accomplish what they planned to do?Were they distracted and how did they get back to work?Did they plan enough time or did they need more time than they thought?<span>Under what conditions did they accomplish the most work.
Hope this helps!!!!!
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<h3><u>Answer;</u></h3>
Potassium chloride
<h3><u>Explanation;</u></h3>
- Potassium Chloride is an ionic compound and has ionic bond which is stronger than covalent bond in ethyl alcohol,water ,ammonia, and thus has the highest boiling point .
- ionic bond is a type of bond that results from the transfer of electrons between metallic atoms and non-metallic atoms.