as a clinical chemist in charge of the testing of blood samples. you are required to mix a solution of sodium chloride with water in the ratio of 2: 5. =2: 52/7 of whole solution chloride 5/7 of whole solution is water780ml = 2/71/7 = 390 ml5/7 = 1950total solution =2730ml780ml = sodium chloride1950ml = water780: 1950ml.
how do i put that in standard form and to an appropriate number of significant figures?

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:

what is the actual question though?