Please help me with these?? Work needs to be shown.

Step-by-step explanation:

7) Area = 615.75 sq. km

πr² = 615.75

3.14*r² = 615.75

r² = 615.75/3.14 = 196

r = √196

r = 14 km

8) circumference = 15.71 yards

πd = 15.71

3.14*d = 15.71

d = 15.71/3.14  = 5 yards

9)Area = 415.48 sq.inches

πr² = 415.48

3.14*r² = 415.48

r² = 415.48/3.14 =  132.31

r = √132.31

r = 11.5 inches

diameter = 11.5*2 = 23 inches

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2

i would be happy to . most people on would also love to i'm sure. if you just want someone who has done algebra before and want a little more personal relationship than just begging strangers for , i can certainly be of service. i do have college myself so i might not be 24/7.