What is the typical spacing for boards when installing board-and-batten siding?

What is the typical spacing for boards when installing board-and-batten siding?
 
  A) 24 o.c. B) 18 o.c. C) 12 o.c. D) 16 o.c.

---

[Ques. 2] When steel wool is used to clean copper tubing, it should be _____.
 
  A) No. 00 B) No. 01 C) No. 02 D) No. 03

---

[Ques. 3] What is the (effective) actual exposure for 10 bungalow style cedar siding?
 
  A) 6-3/8  6-1/2 B) 4-1/2 C) 8  8-1/2 D) 9 -1/2  10-1/2

---

[Ques. 4] Given: A circuit has a voltage of 100 volts across five resistors in parallel (5, 14, 21, 25, and 100 ohms). The total current is _____.
 
  A) 12.71 amps B) 20.2 amps C) 25.3 amps
  D) 36.9 amps

---

[Ques. 5] Two resistances of 30 and 25 ohms are connected in parallel. In series with this combination is a 40 -ohm resistance, and in parallel with this total combination is a 28-ohm resistance. Given a voltage of 1.28 volts, the total current flowing through the circuit is _____.
 
  A) 55 milliamps
  B) 60 milliamps C) 70 milliamps
  D) 95 milliamps