1. Find the rate of change of the area of a square with respect to the lengthz, the diagonal of the square. What is the rate whenz=10?

a) dAdz=z;rate=20

b) dAdz=2z;rate=10

c) dAdz=z;rate=10

d) dAdz=2z;rate=20

e) dAdz=z2-;rate=102-

2. The area of a sector in a circle is given by the formula:A=12r2, whereris the radius andis the central angle measured in radians. Find the rate of change ofAwith respect torifremains constant. What is the rate whenr=6?

a) dAdr=2r; rate=12

b) dAdr=r; rate=6

c) dAdr=r; rate=6

d) dAdr=r2; rate=36

e) Not possible.

3. An object moves along thex-axis, its position at each timet0is given byx(t)=54t4+120t2. Determine the time interval(s), if any, during which the object slows down.

a) (4,43-)

b) (4,23-)

c) (4,83-)

d) (43-,83-)

e) (15,4)

4. An object projected vertically upward from ground level returns to earth in 20 seconds. Find the initial velocity in feet per second.

a) 316

b) 326

c) 320

d) 330

e) 336

5. A falling stone is at a certain instant 120 feet above the ground. Two seconds later it is only 40 feet above the ground. If it was thrown upward with an initial speed of 3 feet per second, from what height was it thrown?

a) 767164feet

b) 773564feet

c) 792764feet

d) 760764feet

e) 799164feet