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1. What does this code print? ``

python
count = 0
y = 0.0
while y <= 0.6:
    count += 1
    y += 0.1
print(count)

``

6578

2. The output goes to a file. In what order do the three lines appear in the file? ``

python
import io
import sys

out = io.TextIOWrapper(sys.stdout.buffer, encoding="utf-8")
out.write("buffered line A\n")
print("direct line B")
out.write("buffered line C\n")
out.flush()

``

buffered line A, buffered line C, direct line Bbuffered line A, direct line B, buffered line Cdirect line B, buffered line A, buffered line Cbuffered line C, buffered line A, direct line B

3. True or false: adding 0.1 to a float ten times, starting from 0.0, gives exactly 1.0.

True, because the rounding errors cancel out after the tenth additionTrue, because 0.1 is stored exactly in binary, so ten tenths add to 1.0True, because a float rounds every sum to the nearest whole numberFalse, because the stored total after ten additions is 0.9999999999999999, not 1.0

4. The program below writes three lines and then calls os._exit(0). The output goes to a file. How many bytes are in the file? ``

python
import os
import sys

for i in range(1, 4):
    sys.stdout.write(f"this line is never flushed {i}\n")
print("program ended")
os._exit(0)

``

87, because each write call sends its line straight to the file0, because the text waits in the buffer and os._exit ends the program before it is sent18, because only the print line reaches the file87, because the program's exit always flushes sys.stdout

5. Which loop prints eleven values from 0.0 to 1.0 with no drift?

x = 0.0, then while x != 1.0: print(x) and x += 0.1. It never ends, because x never equals 1.0 exactly.x = 0.0, then while x <= 1.0: print(x) and x += 0.1. It prints eleven values, but the last is 0.9999999999999999.for x in range(0.0, 1.0, 0.1): print(x). It raises TypeError, because range needs ints.for i in range(11): x = i / 10, then print(x). Each value is rounded once.

Float drift and output in Python