Which situation provides the best evidence that a chemical reaction is taking place? A).A chemical completely dissolves in water and the temperature of the solution remains constant
B).A metal strip bends when heat
C).Two solutions mixed produce a solid
D).A solution freezes in the freezer

answer; i believe that the correct answer is (d) a very small amount of mass

answer; (arch); good luck

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

i think if it were me i whould divide 300 dide 15

step-by-step explanation: