Section 12: Subroutines191
Before you begin, be sure that all of the upper-row keys do not have any functions assigned to them. For example, PROMPT is now assigned to the Σ+ key location. To remove the assignments:
Keystrokes Display
g ASN
 ASN _

ALPHA ALPHA
 ASN _

Σ+
 00 REG 33

Now run the program. Make sure the calculator is in USER mode.
Keystrokes Display
PRGM
 0

XEQ
ALPHA SPEED ALPHA
 A,B,OR C?

A ( Σ+
 RATE?

24791
 24,791 _
The rate.
R/S
 TIME?

2.5
 2.5 _
The time.
R/S
 61,977.5000
Miles in 2.5 hours.
Now run the program (local label B) to find the rate of travel of the first Antarctic continent crossing from Shackelton Base to Scott Base by way of the Pole. The crossing spanned 2,158 miles and took 99 days.
 R = D ÷ T = 2,158 ÷ 99
Keystrokes Display
B ( 1/X
 DISTANCE?

2158
 2,158 _
The distance.
R/S
 TIME?

99
 99 _

R/S
 21.798
Miles per day.
Finally, run the program (local label C) to find the time for a tsunami (a large wave caused by a seaquake) to reach the southern shore of the Pacific Island Iwo. The wave is traveling at a constant 2.25 meters per second and is 300 meters off shore.
 T = D ÷ R = 300 ÷ 2.25