Find the value of each variable.
a. a =10 square root of 3, b=5, c=15, d= 5 square root 3
b. a=10 square root of 3, b=5 square root 3, c=15, d=5 square root 3
c. a=10 square root of 2, b=5 square root 2, c=15, d=5
d. a =10 square root of 3, b=5 square root 3, c=15, d=5