Can someone express 105/20 as a mixed number in simplist form

In δabc, if the length of side b is 3 centimeters and the measures of ∠b and ∠c are 45° and 60°, respectively, what is the length of side c to two decimal places?

The standard distance between studs in a house is 1.5 feet. if you have a set of blueprints for a house that mark every 1.5 feet with 2 in., by how many inches will a 13-foot wall be represented?

According to the general equation for conditional probability if p(anb)=3/7 and p(b)=7/8 what is p(a i b)