Answer:
64
Explanation:
Distance traveled in 2 hours = 2 * 40 = 80 m
Distance traveled in 3 hours = 3 * 80 = 240m
Total distance covered = 240 + 80 = 320m
Total time = 2 + 3 =5 h
Hence avg speed = total distance covered / total time taken
= 320/5 = 64mph
It is due to a lack of providable energy to the next trophic level of the energy pyramid. Primary consumers only obtain around 10% of energy that producers have, and the energy depletes as you move further and further up the food chain, until you reach the tertiary consumers which have the least amount of energy at their disposal, meaning there are less of them than other organisms further down the energy pyramid.
Hope this helped!
Answer:
2
Explanation:
your answer is correct. The overall balanced equation would be:
2Cu +2HNO3 ----> 2CuNO3 +H2
Answer: 0.8M
Explanation:
Given that,
Amount of moles of NaCl (n) = ?
Mass of NaCl in grams = 1.40 g
For molar mass of NaCl, use the molar masses:
Sodium, Na = 23g;
Chlorine, Cl = 35.5g
NaCl = (23g + 35.5g)
= 58.5g/mol
Since, amount of moles = mass in grams / molar mass
n = 1.40g / 58.5g/mol
n = 0.024 mole
Now, given that:
Amount of moles of NaCl (n) = 0.024
Volume of NaCl solution (v) = 30.0mL
[Convert 30.0mL to liters
If 1000 mL = 1L
30.0mL = 30.0/1000 = 0.03L]
Concentration of NaCl solution (c) = ?
Since concentration (c) is obtained by dividing the amount of solute dissolved by the volume of solvent, hence
c = n / v
c = 0.024 mole / 0.03 L
c = 0.8 M (0.8M means concentration is in moles per litres)
Thus, the concentration of the solution is 0.8M
Alexandra requires a total energy of 1350 kcal for the climb
by eating proteins, fats and carbohydrates the amount of calories per gram contributed varies.
Proteins and carbohydrates - 4 calories per gram
fats - 9 calories and gram
This means that by eating the same mass of fats and proteins/ carbohydrats the calories gained from fats is higher.
each bar contains;
<span>50 g of carbohydrates - 4 calories/g x 50 g = 200 calories
10 g of fat - 9 calories/g x 10 g = 90 calories
40 g of protein - 4 calories/g x 40 g = 160 calories
total amount of calories from 1 bar = 200 + 90 + 160 = 450 calories
energy required = 1 350 000 calories
bars required = 1 350 000/450 = 3000
alexandra should consume 3000 bars </span>
