Can you please explain this to me and answer

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

Adesigner charges a one time fee of $200 plus $40 an hour for each project. write an expression to represent how much money the designer will make for a project

Four quarts of a latex enamel paint will cover about 200 square feet of wall surface. how many quarts are needed to cover 98 square feet of kitchen wall and 52 square feet of bathroom wall