Can someone explain how to do these?

Select the correct answer. in the figure, angle k measures 45°. what is the measurement of angle c? a. 38° b. 45° c. 90° d. 98°

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Scale factor of 2 is used to enlarge a figure as shown below the area of is 18 in.²