if the estimated exposure ( mrem )/hr* is 0.28, what is the specimen weight/size?
CREATE TABLE "notes" (
  "specimen_weight_size" text,
  "calculated_activity_bq" real,
  "calculated_activity_ci" text,
  "estimated_activity_gr_api" text,
  "estimated_exposure_m_rem_hr" text
);
SELECT COUNT("specimen_weight_size") FROM "notes" WHERE "estimated_exposure_m_rem_hr"='0.28';