The correct option is A.
Fluorescent lamps have many advantages over incandescent lamps and the options given in B, C and D are part of these advantages. The option given in A is a disadvantage and not an advantage. This is because, as a result of operating at an higher temperature, it will gives out and radiate more heat.
Answer:
The direction of the B-field is in the +y-direction.
Explanation:
The corresponding formula is

This means, we should use right-hand rule.
Our index finger is pointed towards +x-direction (direction of velocity),
our middle finger should point towards the direction of the B-field,
and our thumb should point towards the +z-direction (direction of the force).
Since our middle finger in this situation points towards +y-direction, the B-field should be in +y-direction.

Answer:
T'=92.70°C
Explanation:
To find the temperature of the gas you use the equation for ideal gases:

V: volume = 3000cm^3 = 3L
P: pressure = 1250mmHg; 1 mmHg = 0.001315 atm
n: number of moles
R: ideal gas constant = 0.082 atm.L/mol.K
T: temperature = 27°C = 300.15K
For the given values you firs calculate the number n of moles:
![n=\frac{PV}{RT}=\frac{(1520[0.001315atm])(3L)}{(0.082\frac{atm.L}{mol.K})(300.15K)}=0.200moles](https://tex.z-dn.net/?f=n%3D%5Cfrac%7BPV%7D%7BRT%7D%3D%5Cfrac%7B%281520%5B0.001315atm%5D%29%283L%29%7D%7B%280.082%5Cfrac%7Batm.L%7D%7Bmol.K%7D%29%28300.15K%29%7D%3D0.200moles)
this values of moles must conserve when the other parameter change. Hence, you have V'=2L and P'=3atm. The new temperature is given by:

hence, T'=92.70°C
Area of a circle is
A= pi r^2
so
500m^2 = 3.14 r2
500/pi = r ^2
152.1549...=r^2
square root both sides
r=12.61566...
d=2r
d=25.2
to 3 sig fig