Answer:
B. materials change their properties.
Explanation:
In a chemical change, materials often change their properties because a re-arrangement of atoms takes place.
A chemical change is one in which new kind of matter is formed.
It is always accompanied by energy changes.
- Chemical changes are not reversible.
- They lead to the production of new kinds of matter
- It involves mass changes
- Requires considerable amount of energy
Answer:
31.67 mph
Explanation:
To calculate the average speed of the truck, we must first obtain the total distance travelled by the truck followed by the total time taken for the truck to cover the distance travelled.
The following data were obtained from the question include:
Total distance) = 30 + 45 + 50 + 65 = 190 miles
Total time = 1 + 2 +1 +2 = 6 hours
Average speed =.?
Average speed = Total distance / Total time
Average speed = 190 /6
Average speed = 31.67 mph
Therefore, the average speed of the truck is 31.67 mph
Answer:
n = 12.18 moles
Explanation:
Given that,
The volume of a canister, V = 1 L
The temperature of the canister, T = 100 K
Pressure, P = 100 atm
We need to find the number of moles of gas. Let there are n number of moles. We know that,
PV = nRT
Where
R is gas constant, R = 0.0821 L*atm/mol*K

Hence, there are 12.18 moles of gas.
Answer:
Four times the original amount if only one orange was used
Explanation:
We can assume that the oranges all have equal voltages. Connecting them in series will have an increasing effect on the voltage delivered. In our case, this will produce 4 times the voltage of the circuit when only one orange is used.
Whenever simple cells are connected in series, the voltages of the individual cells are added up to form the voltage of the whole circuit.
Let us assume that the voltage of each of the oranges is approximately 0.9 volts. The Voltage produced when the 4 oranges are joined in series is 0.9 + 0.9 + 0.9 + 0.9 = 3.6 volts
Answer:
Because oxygen is the combustion fuel and glucose is the substrate needed for synthesis of energy as ATPs during cellular respiration.Therefore Guillermo lacks enough energy as ATPs in her body cells, especially skeletal muscles cells to complete the task of ascending the s steps.
For all the mitochondrial in cells(sites of energy production) to receive needed glucose,and other metabolites needed for energy synthesis; an efficient transport system is needed, so that these materials are available immediately, in required amount. This system is called circulatory system.
And for the the supply of combustion fuel (oxygen) needed for the completion of the ATP synthesis mechanisms; respiratory systems which convey oxygen from the external environments to the circulatory system through breathing mechanisms, for distribution is needed.
Thus the doctor needs to test both the circulatory and respiratory systems.
Explanation: