What is power of this elevator in horsepower units

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.

the best answer for these questions would be:

1.            c. is smaller

2.            d) concrete operational

3.            b) interaction with the environment – the children interact with their environment can them learn more.

4.            a) parents who reason openly with children can limit a child’s cognitive ability.