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The vet charges $45 for an office visit and $10 for each vaccination your dog needs. write an eaquation

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)

Zack and tia played chess for 50 min they put the chessboard away at 11: 20 when did they start