Write 0,000000357 in scientific notation​

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?

The longer leg of a 30° 60° 90° triangle is 16 times square root of three how long is a shorter leg

If 3x+8=3x+8 is it one solution or no solution