Round 1.6 to the nearest tenths and 1.64 to the nearest hundredths what was the original number?

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

Aright triangle has an area of 21 m2. the dimensions of the triangle are increased by a scale factor of 4. what is the area of the new triangle

Asap will give brainiest to first person to answer what is the measure of angle b in the triangle? enter your answer in the box.m∠b=