1- State how many significant figures are proper in the results of the following calculation: (15.1)(0.20 – 30.05 + 170.2)

1- State how many significant figures are proper in the results of the following calculation:
(15.1)(0.20 – 30.05 + 170.2)
2- Cos 126.39°
3- Soccer fields vary in size. A large soccer field is 90.3 m long and 83.1 m wide. What is its smallest dimension in inches? (Assume that 1 meter equals 3.281 feet.)
4- Solve: (1.6 x 102) / (3.5 x 103)
5- Solve: (4 x 10-1)2
6- Sin 109.65°
7- Mount Everest, at 29,028 feet, is the tallest mountain on the Earth. What is its height in kilometers? (Assume that 1 kilometer equals 3,281 feet.)
8- What is the exponent of the solution to this expression?
4-2.1 x 45.8
9- What is the height in meters of a person who is 7 ft, 6.7 in. tall? (Assume that 1 meter equals 39.37 in.)
10- State how many significant figures are proper in the results of the following calculation:
(106.7)(98.2) / (46.210)(1.01)
11- Two legs of a triangle are 12.3 meters and 3.7 meters. The angle between them is 99.3 degrees. What is the length of the third side?
12- Tan 21.92°
13- Suppose that your bathroom scale reads your mass as 77.4 kg with a 0.5% uncertainty. What is the uncertainty in your mass (in kilograms)?
14- The speed of sound is measured to be 338.3 m/s on a certain day. What is this in km/h?
15- If the base of a certain ramp is 19.1 meters long, and its height is 4.9 meters, what is the angle in degrees of the incline?