Question

using only these supplies, which question can lauren investigate with an experiment? do large candles or small candles produce more smoke? do candles with thick wicks or with thin wicks produce more smoke? do scented candles or unscented candles produce more smoke?

Explanation:

To determine which question Lauren can investigate with an experiment, we analyze the requirements for a testable experiment (controlling variables, using available supplies). However, since the problem doesn't list the "supplies" Lauren has, we assume a typical setup. But generally, for an experiment, the variable should be controllable with common supplies. If we assume supplies include candles with different wick thicknesses (thick vs thin) but maybe not necessarily different sizes (large/small) or scented/unscented (which might involve different waxes/scents hard to control), the question about wick thickness is more likely testable with basic supplies (as wick thickness can be a more straightforward variable to manipulate with standard candles or by preparing candles with different wick sizes). But since the problem's "supplies" are not given, if we have to choose based on typical experimental design (manipulating one variable, holding others constant), the question "Do candles with thick wicks or with thin wicks produce more smoke?" is a classic experimental question as wick thickness is a variable that can be controlled (using candles with thick vs thin wicks, same wax, same size, etc.), while large/small candles might involve size (harder to control if supplies don't have same - type candles in different sizes) and scented/unscented involves scent (which can be a complex variable).

To conduct an experiment, the variable (wick thickness, candle size, or scent) should be controllable with available supplies. Wick thickness is a more straightforward variable to manipulate (e.g., using candles with thick vs thin wicks, keeping other factors like wax type, candle size constant). Candle size (large/small) may be harder to control if supplies don't have same - type candles in different sizes, and scent (scented/unscented) involves complex factors. So the question about wick thickness is most testable.

Answer:

Do candles with thick wicks or with thin wicks produce more smoke?