What equation could be used to find how many grams of mass is in 15.6 kilograms

Jonah buys a television that costs $445. sales tax in his state is 7 percent. which of the following expressions represent the amount of tax on the television?

If you bought a stock last year for a price of $124, and it has gone down 5.6% since then, how much is the stock worth now, to the nearest tenth?

How to slove in standard form 1x+2y=-8