Four groups of rats are first masses and then fed identical diets except for the amount of vitamin a they receive. each group gets a different amount. after 3 weeks on the diet, the rats’ masses are measured again to see if there has been a decrease. what is the independent variable?

i dont know

explanation:

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.