Ascientist launched an object upward at a speed of 32 ft per second from a height of 240 feet. the height of the object is modeled by the equation h = 240 + 32t – 16t2. after how much time will the object hit the ground? a 3 seconds b 5 seconds c 12 seconds d 20 seconds

B5 seconds

Step-by-step explanation:

h = 240 + 32t – 16t^2

When is this equation 0

0 = 240 + 32t – 16t^2

Factor out 16

0 = -16(-15-2t+t^2)

   = -16(t^2-2t-15)

What 2 numbers multiply to -15 and add to -2

-5*3 = -15

-5+3 =-2

0 = -16(t-5) (t+3)

Using the zero product property

t-5=0   t+3=0

t=5    t=-3

Since time cannot be negative

t=5 seconds

120

Step-by-step explanation:

Each square=x

6g-10g=4g       10g-12g=2g      12-14g=2g

15g-14g=1g       16g-15g=1g       20g-16g=4g

(4x3)+(2x8)+(2x11)+(1x23)+(1x19)+(4x20

12+16+22+23+19+8=1000

x=1000

1000÷100=10

1 box = 10

4×30=120

(I got this answer through help of others, it is not truly mine)