Is there a fast way to figure out 197 times 4 in mental math

Acable company wants to provide cell phone service for residents on an island. the function for the cost of laying the cable from the island to the mainland is c(x)= 6.500 square root x2+4, where x represents the length of the cable in feet. what are the domain and range of the function? a) domain: all real numbers range: all real numbers greater than or equal to 17,000 b) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 17,000 c) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 13,000 d) domain: all real numbers greater than or equal to 13,000 range: all real numbers greater than or equal to 0

Sienna planned a trapezoid-shaped garden, as shown in the drawing below. she decides to change the length of the top of the trapezoid-shaped garden from 32 ft to 24 ft. which expression finds the change in the scale factor?

Ivan and jeff buy a package of 8 pens for $4.00. ivan wants 5 of the pens, and jeff wants 3.how much should each student pay?