How long does it take a message to travel from earth to a spacecraft at mars at its closest to earth

An automobile steering wheel is shown. what is the ideal mechanical advantage? if the ama is 8, what is the efficiency of the steering wheel?

The number of passengers who arrive at the platform of a subway station for the 10 am train is a random variable with a mean of 120 and a variance of 16. find the lower bound of the probability that there will be between 100 and 140 passengers (round off to second decimal place).

Wind and moving water provide energy. question 1 options: chemical mechanical thermal none of the above