99.7% of 7-year-old children are tall.

99.7% of 7-year-old children are between 3.8 ft and 4.1 ft = 45.6 inches and 49.2 inches

Step-by-step explanation:

The 99.7% of 7 year old children are usually between the height of 3.8 feet and 4.1 feet. That is, between 45.6 to 49.2 inches tall.

To convert feet to inches, multiply the length in feet by 12.0.

So, 3.8 feet to inches in formula = 3.8 x 12.0.

Thus, for 3.8 feet in inches = 3.8 ft x 12.0 = 45.6 inches

                                                 1           1ft

And 4.1 feet in inches      = 4.1ft  x 12.0   = 49.2 inches

                                              1          1ft

There is no much difference in the heights of the 7-year-old boys and girls.

option (a)

step-by-step explanation:

step 1:   take 2 number whose product equal to 25..

and sum of those two number are -10

step: 2 for example here if we take 5,5 are the number,,

5*5=25

and

5+5=10

but we need -10

so if we take   -5,-5

so -5*-5=25

and -5+(-5)=-10

s0

come the equation

replace -10x by these number

like -5x -5x+25

take common

x(x-5)-5(x-5)=0

(x-5)(x-5)=0

set the two equations for y equal to each other. solve for x. this will be the x-coordinate for the point of intersection. use this x-coordinate and plug it into either of the original equations for the lines and solve for y.