How many different standards have a PM of 0.02 g/kWh?
CREATE TABLE table_2780146_6 (standard VARCHAR, pm__g_kwh_ VARCHAR)
SELECT COUNT(standard) FROM table_2780146_6 WHERE pm__g_kwh_ = "0.02"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_2780146_6 (standard VARCHAR, pm__g_kwh_ VARCHAR) Question: How many different standards have a PM of 0.02 g/kWh? [/INST] SELECT COUNT(standard) FROM table_2780146_6 WHERE pm__g_kwh_ = "0.02" </s>