A researcher tests whether speech therapy helps toddlers' vocabulary. A sample of toddlers who receive speech therapy know = 24.4 words, while a sample of toddlers who don't receive speech therapy know = 21.7 words (t(28) = -2.66, p = .036, d = -.80). Explain what this results means. (Hint: using terms such as: reject/fail to reject, null hypothesis, significant/non-significant, more/less, vocabulary)