What is the probability that the coin lands on heads and Alyssa chooses a red block? Enter the answer, as a decimal, in the box.

To answer this question, we need to know the probability of each independent event.

1. The probability that a coin lands on heads is typically 1/2 (or 0.5 in decimal form) because a standard coin has two sides: heads and tails.

2. The probability that Alyssa chooses a red block depends on the total number of blocks and how many of them are red. Without this information, we can't calculate the exact probability.

Assuming that the blocks are equally likely to be chosen, and there are 'r' red blocks out of a total of 'n' blocks, the probability that Alyssa chooses a red block would be r/n.

The probability of both events happening (the coin landing on heads and Alyssa choosing a red block) is the product of their individual probabilities. So, if P(H) is the probability of the coin landing on heads and P(R) is the probability of Alyssa choosing a red block, the probability of both events happening is P(H) * P(R) = 0.5 * (r/n).

Without knowing the values of 'r' and 'n', we can't provide a numerical answer.