Why are electromagnets more useful than permanent magnets in many modern technologies?
A. A power supply is not necessary to use an electromagnet.
B. Electromagnets can be turned on and off by controlling the
current.
C. Permanent magnets with the same strength are heavier.
D. The strength of the magnetic field is more consistent in
permanent magnets.

Sasha has just gotten a new job in a nearby city. after comparison shopping, she found that renting a nice two-bedroom apartment would cost around $800 per month. her utilities would cost about $150 per month. sasha has enough money saved for a down payment, and she found that she can buy a three-bedroom house or condo with a mortgage payment of $1,000 per month, including taxes and homeowner's insurance. her utilities would cost about $200 per month. what is the advantage of buying the house over renting the apartment?