Easy question the first person to answer it right gets 10 points: 1+2+3+4+5+6+7+8+9+10=?

Sketch one cycle if the cosine function y=2cos2theta

Players on the school soccer team are selling candles to raise money for an upcoming trip. each player has 24 candles to sell. if a player sells 4 candles a profit of$30 is made. if he sells 12 candles a profit of $70 is made

How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?