Final answer:
Roofing cement is not commonly used to secure the layers of shingles to each other; it is mainly used for repairs and sealing around roof protrusions. Shingles are primarily attached with nails or staples.
Step-by-step explanation:
The statement that roofing cement is commonly used to secure the layers of shingles to each other is false. Roofing cement is typically used for patching or repairing leaky roofs, sealing around vents, chimneys, and other roof projections, rather than securing layers of shingles. The primary method of attaching shingles is through the use of nails or staples. However, roofing cement may be used to adhere the bottom layer of shingles to the drip edge or to glue down loose shingle tabs in high-wind areas, but it's not the standard practice for securing all the layers of shingles to each other.