Will give brainliest answer. a ball is thrown into the air with an upward velocity of 28 ft/s. its height (h) in feet after t seconds is given by the function h = –16t² + 28t + 7. how long does it take the ball to reach its maximum height? what is the ball’s maximum height? round to the nearest hundredth, if necessary. a- reaches a maximum height of 7 feet after 1.75 seconds. b- reaches a maximum height of 43.75 feet after 0.88 seconds. c- reaches a maximum height of 17.5 feet after 0.88 seconds. d- reaches a maximum height of 19.25 feet after 0.88 seconds.

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12

that is the sum

step-by-step explanation:

there are no other answers without knowing the variables values