(urgent 75 points)you are given two same party balloons (one filled with helium and the

second is empty and rolled), the scale, graduated mass of 100 grams, and

a pile of paper clips. show how you would:

• calculate the volume of the balloon (no ruler).

• how many balloons you would need to lift 126lbs person?

If a rock is thrown upward on the planet mars with a velocity of 12 m/s, its height (in meters) after t seconds is given by h = 12t − 1.86t2. (a) find the velocity of the rock after two seconds. m/s (b) find the velocity of the rock when t = a. 12−3.72a m/s (c) when will the rock hit the surface? (round your answer to one decimal place.) t = s (d) with what velocity will the rock hit the surface? m/s