Answer and Explanation Please

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics

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=

Measure a and b and find their sum. how are the angles related?