Does anyone know what number 4 is?

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?

Hurry the figure shows the front side of a metal desk in the shape of a trapezoid.what is the area of this trapezoid? 10 ft²16 ft²32 ft²61 ft²

Order the integers from least to greatest. =0 =1 =2 =3 = -3