Find the domain and graph of F(t)=t/|t|​

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

The volume of a cube is 8 in to the 3rd power. how long is each side?

Similarly fie each expression 18,19,20