Rank the metals from most reactive (1) to least reactive (3) tantalum niobium dubnium

During your summer internship for an aerospace company, you are asked to design a small research rocket. the rocket is to be launched from rest from the earth's surface and is to reach a maximum height of 910 m above the earth's surface. the rocket's engines give the rocket an upward acceleration so it moves with acceleration of 16.0 m/s2 during the time t that they fire. after the engines shut off, the rocket is in free fall. ignore air resistance.

How is acceleration calculated? a. initial velocity - final velocity / timeb. initial velocity + final velocity / timec. final velocity - initial velocity / timed. final velocity / timele select the best answer from the choices provided0oood00save and exitnextmark this and return

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.