Please answer this! Im desperate UvU,

If there are 12 moths and some have 31 days and others have 30 days how many have 28 days?

Kelly is a salesperson at a shoe store, where she must sell a pre-set number of pairs of shoes each month. at the end of each work day the number of pairs of shoes that she has left to sell that month is given by the equation s=300-15x , where s is the number of pair of shoes kelly still needs to sell and x is the number of days she has worked that month. what is the meaning of the number 300 in this equation

The map shows the location of the airport and a warehouse in a city. though not displayed on the map, there is also a factory 112 miles due north of the warehouse.a truck traveled from the warehouse to the airport and then to the factory. what is the total number of miles the truck traveled?